John Brennan was also critical of ‘technological capabilities’ that make it difficult for surveillance agencies to track potential terrorists.
Photograph: Win McNamee/Getty Images

The director of the CIA has criticised “hand-wringing” over the role of spy agencies in hunting terrorists and called for legal constraints on surveillance to be reviewed in the wake of last week’s Paris attacks.

John Brennan’s comments on Monday represent the most significant pushback yet against recent reforms of a surveillance programme that swept up millions of Americans’ telephone records and was exposed by former National Security Agency contractor Edward Snowden. They came as pressure grew on internet companies in Silicon Valley to share users’ data and prompted civil liberties campaigners to warn against an overreaction.

“I do think this is a time for particularly Europe, as well as here in the United States, for us to take a look and see whether or not there have been some inadvertent or intentional gaps that have been created in the ability of intelligence and security services to protect the people that they are asked to serve,” America’s top spy told a summit at the Center for Strategic and International Studies thinktank in Washington.

In a reference to whistleblower Snowden, he continued: “And in the past several years, because of a number of unauthorised disclosures and a lot of hand-wringing over the government’s role in the effort to try to uncover these terrorists, there have been some policy and legal and other actions that are taken that make our ability collectively, internationally, to find these terrorists much more challenging. And I do hope that this is going to be a wake-up call, particularly in areas of Europe where I think there has been a misrepresentation of what the intelligence security services are doing by some quarters that are designed to undercut those capabilities.”

Brennan suggested that Europe’s refugee crisis has intensified the need for effective surveillance of Islamic State (Isis). Using the alternative acronym of Isil, he said: “A lot of our partners right now in Europe are facing a lot of challenges in terms of the numbers of individuals who have travelled to Syria and Iraq and back again, and so their ability to monitor and surveil these individuals is under strain.

“Now, I know the French are going to be looking at what might have slipped through the cracks. But I can tell you that it’s not a surprise that this attack was carried out from the standpoint of we did have strategic warning. We knew that these plans or plotting by Isil was under way, looking at Europe in particular as the venue for carrying out these attacks. But I must say that there has been a significant increase in the operational security of a number of these operatives and terrorist networks as they have gone to school on what it is that they need to do in order to keep their activities concealed from the authorities.

“And as I mentioned, there are a lot of technological capabilities that are available right now that make it exceptionally difficult, both technically as well as legally, for intelligence and security services to have the insight they need to uncover it.”

Brennan was not alone in the intelligence community on Monday in claiming that Snowden had caused damage and suggesting the moment demands a rebalancing. But civil liberties activists urged caution. Naureen Shah, director of Amnesty International USA’s security and human rights programme, acknowledged the need for governments to assess their approach in the aftermath of major attacks but said: “What we don’t want to see is government using the Paris attacks as a pretext for extending surveillance authorities or pushing back against reforms that even the government acknowledged as necessary.”

Some of the hawkish responses to events in Paris “raise a question of whether there’s an exploiting of public fear and anger and anxiety to push legislation through”, she added.

At least 129 people were killed in the attacks carried out by at least eight gunmen nearly simultaneously at a stadium, a concert hall and restaurants in Paris on Friday night. Isis appeared to warn in a new video on Monday that countries taking part in airstrikes against Syria would suffer the same fate and specifically pledged to target Washington.

While there has been no evidence of an imminent threat in the US, Brennan acknowledged: “I certainly would not consider it [Paris] a one-off event. It is clear to me that Isil has an external agenda, that they are determined to carry out these types of attacks. This is not something that was done in a matter of days.

“This was something that was deliberately and carefully planned over the course, I think, of several months, in terms of making sure that they had the operatives, the weapons, the explosives, the suicide belts. And so I would anticipate that this is not the only operation that Isil has in the pipeline. And security intelligence services right now in Europe and other places are working feverishly to see what else they can do in terms of uncovering it.”

Despite intelligence successes such as the apparent killing of Isis’s notorious executioner Mohammed Emwazi last week, there were other calls for an overhaul of spy operations at home and abroad following the atrocity in France and the suspected involvement of Isis in the downing of a Russian plane in the Sinai.

Commercial encryption ‘that we can’t break’

The intelligence community’s biggest Democratic supporter in Congress, Senator Dianne Feinstein, criticised technology companies for developing encryption technology. “If you create a product that allows these monsters to behave in this way, that’s a big problem,” the California senator told MSNBC in an interview that also saw her call for more US ground troops in Syria.

Her views were echoed by William Bratton, the commissioner of the New York police department, who claimed that tracking suspects with technology is becoming more and more difficult because of end-to-end encryption, which he believes was “a significant factor” in planning the Paris attacks.

“Basically, the technology has been purposely designed by our manufacturers so that even they claim they can’t get into their own devices after they’ve built them,” Bratton told MSNBC, describing terrorists’ ability to “go dark” as a huge obstacle to law enforcement.

“Every day we lose the ability to gather intelligence,” he said. “You have to be on the offence. Offence is intelligence. We are losing a lot of that intelligence momentum because of that issue.”

He appealed to companies in Silicon Valley to change the software so it can be monitored: “They need to work with us right now. In many respects, they are working against us.”

Michael Morell, a former deputy director of the CIA now at Beacon Global Strategies, told CBS television: “I don’t think it’s possible to overstate the significance of what’s happened in the last two weeks. Our strategy to defeat them … degrade them is simply not working.”

The terrorists’ ability to “communicate under the radar” is a huge problem, he added, since they seem to be using commercial encryption “that we can’t break. I think this is going to open an entire new debate about security versus privacy.”

Morell said: “We need to have a public debate about [encryption] … We have, in a sense, had a public debate. That debate was defined by Edward Snowden … and the concern about privacy. I think we’re now going to have another debate about that. It’s going to be defined by what happened in Paris.”

Republican presidential candidate Jeb Bush also weighed into the debate over the reach of the NSA. “I think we need to restore the metadata programme, which was part of the Patriot Act,” he told MSNBC. “It expires in the next few months. I think that was a useful tool to keep us safe and also to protect civil liberties.

“Look, any type of act like what happened in Paris or happened in other countries over the last few weeks creates a dramatic change in economic outlook for the country as well. There is a lot riding on this. So I think we can have the proper balance of protecting privacy rights and making sure that we use all of the tools of intelligence to keep us safe.”